Temperatures are fairly mild throughout the year, with more frequent rains in autumn and spring, some snowfalls in winter and not extremely hot summers. The average summer temperature is 20 ºC and 8ºC in winter.
The weather in Vitoria-Gasteiz
http://canalmeteo.elcorreodigital.com/ciudad.php?id_ciudad=104
National Institute of Meteorology: Weather forecast for Vitoria-Gasteiz
http://www.aemet.es/es/eltiempo/prediccion/municipios/vitoria-gasteiz-id01059
The weather in the Basque Country
http://www.euskalmet.euskadi.net